In ancient times, the horse was used to transport people, tools, weapons, and in some cases, even as a shield against Indian arrows. Nowadays there are several functions for the horse such as sport horses used for racing, rodeo, jumping, polo, riding, work, shooting, among others. In the events that use sport horses, they usually use the teeth as an indicator to calculate their ages. The age of the horse is also relevant in the purchase and sale of horses, however, most buyers or sellers do not know how to calculate their age. The objective of this project was to elaborate a manual for estimating the age of equines through their teeth. This manual aims to facilitate the determination of the age of horses with the sole purpose of serving as a tool for sporting events, producers, technicians and the general public.